Apparatus for winding sewing thread upon bobbins

ABSTRACT

An apparatus for winding sewing thread upon a bobbin is provided with means for holding the thread end when starting the winding and until the thread is securely anchored on the bobbin. Said means comprises a spring clip fastened to the rotor turning the bobbin and located thereon at a greater radius than the bobbin. The thread end part stretched between the bobbin and said holding means can be caught by a stationary member movable into the path described by said thread end, whereby the thread end is disengaged from the holding means and can be covered by the following thread turns upon the bobbin.

atent 11 1 O I nlted States [1 11 3,7419% Johansson June 26, 1973 1APPARATUS FOR WINDING SEWING 2,558,039 6/1951 Carroll 112/2525 THREADUPON BOBBINS 2,584,320 2/1951 2,867,184 1/1959 lhvenwfl i 3 3 6 3 22 2hblemg 2,983,455 5/1961 Herbst 242/22 3233 re FOREIGN PATENTS ORAPPLICATIONS 803,156 10/1958 Great Britain 112/218 A [22] Filed: June15, 1971 2 App}. NM 153 2 Primary Examiner-Stanley N. GilreathAttorney-Cushman, Darby & Cushman [30] Foreign Application Priority DataJune 16, 1970 Sweden "8331/70 [57] ABSTRACT An apparatus for windingsewing thread upon a bobbin 52 us. c1....- 242/20, 1 12/252, 242/21, isprovided with means for holding the thread end when 242/22 242/49starting the winding and until the thread is securely an- 51 Int. ClB65h 54/00, B65h 63/08 ehored on the bebbin- Said means comprises aspring [58] Field of Search ..242/20-24, p fastened to the rotor turningthe bobbin and 3 39 2 3Q 49; 112/218 A 2525 cated thereon at a greaterradius than the bobbin. The thread end part stretched between the bobbinand said '5 R f en Ci d holding means can be caught by a stationarymember UNITED STATES PATENTS movable into the path described by saidthread end, 242 20 whereby the thread end is disengaged from the holdingg f means and can be covered by the following thread 2,261,680 0 egro eturns p the bobbin.

11/1941 Hale 112/2525 7 Claims, 9 Drawing Figures PATENTEU JUN 2 6 I975Fig. 2

APPARATUS FOR WINDING SEWING THREA UPON BOBBINS The invention relates toan apparatus for winding of sewing thread upon bobbins for sewingmachines, particularly for such bobbins for bottom thread as should beinserted into a shuttle or a rotary hook. The apparatus constitutes aunit dependent of the sewing machine and comprises a driven rotor with acenter stem" upon which one bobbin at a time can be removably attachedin such a manner as to be carried along in the rotation of the rotor.

The problem forming the basis of the design of the apparatus isconnected therewith that often the thread is so sleek that it isdifficult to get the first thread turns to stick to the bobbinsufficiently tight for the subsequent drawing forth of the thread. Thisis particularly true for thread consisting of artificial fiber, such asnylon thread.

According to the invention said problem is solved in principle, bytemporarily attaching the thread end to the rotor laterally of thelocation of the bobbin-Then, one does not have to rely upon the frictionof the first wound thread turns against the bobbin core, but the threadend will be securely held fast to the rotor until a great number ofturns have been wound upon the bobbin core andthere is no longer a riskof the thread slipping thereagainst. Then the thread end is let loose,so that it will be covered by the following thread turns upon thebobbin.

Further characteristic features of the invention are stated in theconcluding claims and will also appear from the following detaileddescription of two embodimentsshown in the accompanying drawings, of thewinding apparatus according to the invention.

. FIG. 1 is an elevational view of a first embodiment of the apparatus,

FIG. 2 shows a detail as viewed from the line II-II in FIG. 1,

FIG. 3 is a plan view of the apparatus,

FIGS. 4 and 6 are plan views of certain parts of the apparatus shownindifferent working positions,

FIG. is a partially sectional end view taken from the line V-V in FIG.4,

FIG. 7 is an end view taken from the line VII-VII in FIG. 6, certainparts being partially broken away,

FIG. 8 is a fragmentary elevational view taken on the line VIII-VIII inFIG. 3 and FIG. 9 is a diagrammatic view of a second modified embodimentof the apparatus.

In the drawings, 11 designates the rotor of the apparatus which by meansof a vertical shaft 13 is journalled in a hub 15 projecting from thebase plate 17 of the apparatus. Attached thereto is also an electricmotor 19 which turns the rotor by means of a belt transmission 21. Theupper end of the rotor shaft forms a center stem 23 upon which a bobbinconsisting of a cylindrical core 25, a lower flatflange 27 and an upperflat flange 29, can be applied. The stem 23 is split and its halves areresiliently pressed against the sleeve 25 of the bobbin, so that thebobbin is securely held but can easily be drawn off by hand when filledwith thread. During the winding the sewing'thread 31 supplied from astock bobbin (not shown) runs over a thread stretcher 33 and from therein a straight path to the bobbin attached to the rotor. Of course, thefrictional engagement of the bobbin with the center stem 23 issufficient for overcoming the resistance of the thread stretcher 33 andfor pulling forth the sewing thread.

The motor 19 is thrown-in by a microswitch 35 actuated when manuallydepressing an operating lever 37 which is pivoted about a vertical pin39. A coiled spring 38 fastened to a projection 41 upon the operatinglever 37 tries to return the same upwardly, but normally the operatinglever is locked in the position shown in FIG. 1 by means of a lever 43which is movable in the horizontal plane and which places itself above aprojection 45 upon the operating lever 37. The lever 43 is under theinfluence of a coiled spring 47 which strives to retain the lever in theposition shown in FIGS. 1 to 3. By means of a tumable vertical bolt 49the lever 43 is connected to a feeler arm 51 swingable in the horizontalplane, the end of which can swing in between the two flanges 27, 29 ofthe bobbin and abut against the outermost thread turns upon the bobbin.When the bobbin is empty, the feeler arm 51 takes the position shown inFIG. 4. According as the bobbin is being filled, the feeler arm is swungcounter-clockwise as seen from above, and when the bobbin is full, ithas swung the lever 43 connected thereto into the position shown indotted lines in FIG. 2, in which the latter is positioned above adownwardly inclined end 53 of the projection 45. Then the spring 38overcomes the force of the spring 47 and returns the operating lever 37to its uppermost position, whereby the switch is thrown out and themotor stopped. Due to inertia the rotor 11 continues to turn until astud 55 upon its bottom face is caught by a notch 57 in the operatinglever 37, whereby the rotor is stopped in a predetermined angularposition. When the projection 45 is raised, its downwardly bent end 53will push the lever 43 aside resulting in that the feeler arm 51 isswung further out, viz. into the position shown in FIG. 3, in which itis positioned completely beyond the bobbin so as not to prevent theremoval thereof from the center stem 23.

Next to the center stem 23 rotor 11 has a recess 59 (FIGS. 4 and 5), inwhich the lower end flange 27 of the bobbin fits. Adjacent to and aroundsaid recess the rotor is formed with a concentric conical face 61merging into a flat annular face 63 perpendicular to the axis of therotor.

Arranged at the periphery of said flat face is the thread end holdingmeans which is an essential element of the invention. The same consistsof a thin flat blade spring 65 held applied to the flat face 63 of therotor 11 by a screw 67 and guided by pins 69, 71 projecting throughcorresponding holes in the blade spring. The spring face is of an acuateshape with the outer edge extending close to the periphery of the rotorand the inner edge concentric thereto and distant from the conical face61. The extreme end 73 of the spring is bent slightly upwards so as toform a thread-catching gap, and the spring can yield resiliently and bepartly raised from the rotor face. A thread caught by said spring clipcan be drawn into the resilient gap until it is stopped by the pin 69.In said position the clamping force of the spring is sufficient forsecurely holding the thread and for overcoming all resistances to itsdrawing forth.

At the side of the part of the rotor periphery where the thread endholding clip 65 is situated in the stopped position of the rotor (FIG.3) there is a wire fork 75, in the gap of which a knife 77 is inserted.As shown in FIG. 8, the wire fork 75 which is attached to the bottomplate 17 of the apparatus by means of a post 74, consists of two legs,one above the other, the lower one 76 being situated at about the samelevel as the rotor face 63. The knife 77 serves to sever the thread whena filled bobbin should be removed. To this end the bobbin is grasped bythe hand of the operator and moved outside of the wire fork 75 in such amanner that the stretched thread is introduced into said fork and hitsthe knife 77 at the bottom of the fork. Simultaneously therewith thethread has been brought in under the free end of the blade spring 65. Inthe final position shown in FIG. 3, the severed thread end is clampedbeneath said spring and extends therefrom in a straight path to thethread stretcher 33. In said path the thread lies below as well aslaterally of the space 59, into which a new bobbin should be inserted,thus forming no obstacle thereto. Apparently a provision therefor isthat in the stopped position of the rotor the thread end holding clip 65is placed laterally of and at the greatest possible distance from thenormal thread supply direction, i.e., as seen from the center stem 23,in a direction transverse to and preferably forming an angle of 90 to120 to the direction towards the thread stretcher 33.

FIG. 3 shows the initial position in which a new and empty bobbin hasbeen pushed upon the center stem of the rotor. When depressing theoperating lever 37, the motor is started and begins to turn the rotor 11in the counter-clockwise direction, as seen from above. Simultaneouslythe released feeler arm 51 is swung under the action of the spring 47into abutment with the core of the bobbin (position of FIG. 4). When therotor moves from its position of rest, the straightly extending thread31 is first swung inwardly towards the bobbin and will presently beapplied against the conical face 61 which guides the thread in such amanner that the same is raised from the flat face 63 and is'guidedtowards the bobbin without being hampered by the lower flange of thebobbin which is sunk into the recess 59. During the continued motion ofthe rotor the thread is bent around the bobbin (see FIG. 4) and threadis drawn forth and wound up while the thread end 79 extending from thebobbin to the clip 65 is still held by said clip.

A post 81 attached to the bottom plate supports a horizontal pin 83,upon which a yoke 85 is pivoted. Extending therefrom is an arcuate metalwire forming a catch 89 for catching the thread end 79. Said catch isbent concentrically to the rotor and extends along an arc of a circle ona slightly greater radius than the conical face 61. The catch can beswung from a lifted position (FIG. 5) into a lowered position (FIG. 7)by cooperation with the feeler arm 51. The latter has a lateralprojection 91 which is applied against the flat side of the yoke 85 andkeeps said side vertical and thereby the catch raised as long as thefeeler arm 51 still is positioned deep into the bobbin. According asmore thread is wound up onto the bobbin, the feeler arm 51 is pushedaside and the projection 91 is retracted, so that the yoke 85 with thecatch 89 drops down into the position of FIG. 7. The outermost free endof the catch will then be placed in the path of the thread end 79extended between the bobbin and the holding clip 65, so that the threadend slides up thereon and is drawn out of engagement with the clip 65.Then the free thread end will be dragged in and covered by the followingwinding turns up the bobbin.

The modified embodiment shown in FIG. 9 corresponds to the one justdescribed, in respect of the design of the upper side of the rotor, thespring clip attached thereto, the feeler arm and the thread catch.Therefore, these members have been designated by the same referencenumerals as in FIGS. 1 to 8.

In the modified embodiment, the mounting of the apparatus comprises atop plate 12 having a through circular aperture 14, in which the rotor11 is inserted so that its peripheral plane face 63 is flush with theupper face of the plate 12. A spring clip 16 similar to the spring clip65 is attached to the plate 12 by means of screws 18. A pin 20 securedto the plate 12 projects through a hole 22 in the clip and forms a stopfor the thread 31 when drawn into the gap of the clip. The point 24 ofthe clip projects somewhat beyond the edge of the plate 12, whichfacilitates the introduction of the thread into the clip when the fullbobbin is being taken out of the apparatus. On the outside of the clip16 and in the vicinity of the stop pin 20 there is a fixed knife 28, bywhich the thread is cut in connection with the introduction of thethread into the clip 16 and the removal of the bobbin. The clip 16 andthe thread stretcher 33 are positioned on opposite sides of the rotor 11and so that the thread 31 stretched in a straight path therebetweenextends like a chord over the plane face of the rotor. At anintermediate point the thread'is raised slightly from the face of theplate 12 by a raised ridge 30 attached thereto. Therefore, the springclip 65 can pass under the thread on the righthand side of rotor,whereas it will catch the thread at the left-hand side where the threadis held close to the rotor face by the fixed spring clip 16.

The embodiment of FIG. 9 differs from the embodiment first describedalso in that the free end of the spring clip 65 leads in the rotationalmovement and in that the rotor has no predetermined position of rest.When the rotor is started in order to wind thread upon an empty bobbinplaced upon the center stem 23 of the rotor, the clip 65 may take anyposition and has no hold of the thread. Only after the rotor has turnedpart of one revolution, the tip of the clip 65 will hit the thread stillheld by the fixed clip 16. This is the moment shown in FIG. 9. Next thethread will be drawn further into the gap of the spring clip 65 and whenthe end position therein is reached, the thread will be drawn out of thefixed clip 16. Thus the hold of the cut thread end has been transferredto the spring clip 65 on the rotor. The winding of the thread upon thebobbin and the releasing of the thread end then take place in exactlythe same way as has been described with reference to FIGS. 3, 4 and 6.

I claim 1. Apparatus for winding of sewing thread upon a bobbin for asewing machine, comprising a base structure, a rotor mounted forrotation therein, a driving means for said rotor, a stem coaxiallyattached to said rotor and suitable for insertion into said bobbin forfrictional engagement therewith, a thread end holding means attached tosaid rotor in a position at a greater distance from the axis of therotor than the radius of the bobbin, a catching member carried by saidbase structure and mounted for displacement from an inactive positioninto an active position lying in the path described by the thread endstretched between the bobbin and said holding means, and means formoving said catching member into said active position for disengagingthe thread end from said holding means during the run of the rotor.

2. Apparatus as claimed in claim 1 wherein said rotor has a peripheralplane face and said thread holding means comprises a blade spring, oneend part thereof being connected to said rotor and another part thereofbeing resiliently applied against said peripheral plane face of therotor, said spring having a bentout end for guiding the thread into aposition in the gap of said holding means wherein-it is clasped withfriction.

3. Apparatus as claimed in claim ll, wherein the rotor is shaped with acentral recess and with a concentric conical guiding face locatedbetween said stem and said holding means for deflecting the threadstretched to said holding means axially past the end flange of thebobbin inserted in said recess in the rotor, when forming the firstwinding turn of the thread around the bobbin.

4. Apparatus as claimed inc'laim 1, further comprising a feeler memberfor engagement with the outermost thread turns upon the bobbin, saidfeeler member being operatively connected to said catching member fordisplacing the same into said active position when having itself beendisplaced by the thread a predetermined distance corresponding to adesired number of thread turns having been wound up on the bobbin.

5. Apparatus as claimed in claim 1, further comprising a second threadend holding means, said second thread end holding means being fixed tothe base structure of the apparatus in a position exterior of and closeto the periphery of the rotor.

6. Apparatus as claimed in claim 5, wherein a knife for severing thethread is supported by the base structure of the apparatus close to saidsecond thread end holding means.

7. Apparatus as claimed in claim 5, wherein the rotor has a peripheralflat face, to which the thread holding means is attached, the basestructure comprising a flat face located flush with said peripheral flatface of the rotor, and said second thread end holding means comprising ablade spring attached to and held applied to said flat face of the basestructure.

1. Apparatus for winding of sewing thread upon a bobbin for a sewingmachine, comprising a base structure, a rotor mounted for rotationtherein, a driving means for said rotor, a stem coaxially attached tosaid rotor and suitable for insertion into said bobbin for frictionalengagement therewith, a thread end holding means attached to said rotorin a position at a greater distance from the axis of the rotor than theradius of the bobbin, a catching member carried by said base structureand mounted for displacement from an inactive position into an activeposition lying in the path described by the thread end stretched betweenthe bobbin and said holding means, and means for moving said catchingmember into said active position for disengaging the thread end fromsaid holding means during the run of the rotor.
 2. Apparatus as claimedin claim 1 wherein said rotor has a peripheral plane face and saidthread holding means comprises a blade spring, one end part thereofbeing connected to said rotor and another part thereof being resilientlyapplied against said peripheral plane face of the rotor, said springhaving a bentout end for guiding the thread into a position in the gapof said holding means wherein it is clasped with friction.
 3. Apparatusas claimed in claim 1, wherein the rotor is shaped with a central recessand with a concentric conical guiding face located between said stem andsaid holding means for deflecting the thread stretched to said holdingmeans axially past the end flange of the bobbin inserted in said recessin the rotoR, when forming the first winding turn of the thread aroundthe bobbin.
 4. Apparatus as claimed in claim 1, further comprising afeeler member for engagement with the outermost thread turns upon thebobbin, said feeler member being operatively connected to said catchingmember for displacing the same into said active position when havingitself been displaced by the thread a predetermined distancecorresponding to a desired number of thread turns having been wound upon the bobbin.
 5. Apparatus as claimed in claim 1, further comprising asecond thread end holding means, said second thread end holding meansbeing fixed to the base structure of the apparatus in a positionexterior of and close to the periphery of the rotor.
 6. Apparatus asclaimed in claim 5, wherein a knife for severing the thread is supportedby the base structure of the apparatus close to said second thread endholding means.
 7. Apparatus as claimed in claim 5, wherein the rotor hasa peripheral flat face, to which the thread holding means is attached,the base structure comprising a flat face located flush with saidperipheral flat face of the rotor, and said second thread end holdingmeans comprising a blade spring attached to and held applied to saidflat face of the base structure.